1. Field of the Invention
The present invention relates to electrical systems in which first and second sub-systems are connected together via an electrical connector assembly.
2. State of the Art
In such systems, use is made, in a wide range of applications, of an electrical connector assembly which comprises first and second parts having complementary, interengaged terminals.
A drawback of such connector assemblies is that conduction can easily occur between adjacent terminals of one or other of the two connector parts, for example due to corrosion of the terminals where they are exposed to atmospheric conditions. In many safety-critical applications, such conduction may have catastrophic effects: one such application is where the connector assembly is used between the electrical drive motor of a motorised wheel chair, and an electrical controller for the motor.
In accordance with the present invention, there is provided an electrical system comprising:
a) first electrical means and second electrical means;
b) an electrical connector assembly comprising first and second connector parts, said first connector part having first and second terminals and said second connector part having at least a first terminal which is complementary with and interengaged with said first terminal of said first connector part;
c) an electrical conductor extending from said first electrical means to said first terminal of said first connector part and an electrical conductor extending from said first terminal of said second connector part to said second electrical means; and
d) a voltage detecting means;
said second terminal of said first connector part being connected to said voltage detecting means and said voltage detecting means detecting a change in voltage at said second terminal caused by a change in conduction between said second terminal and said first terminal of said first connector part, said second terminal of said first connector part being otherwise unconnected.
The above-mentioned second terminal of the first connector part is free apart from its connection to the voltage detecting means. Thus, in the event that the terminals start to corrode and a conductive path is developed between the first and second terminals of the first connector part, the voltage detecting means will detect a change in voltage on the second terminal.
Preferably the voltage detecting means comprises means for detecting an increase in voltage of more than a predetermined amount.
The voltage detecting means may instead comprise means for detecting a decrease in voltage of more than a predetermined amount.
Preferably the voltage detecting means comprises means to provide an alarm when the voltage change exceeds said predetermined amount.